Water-expelling mudguard for motor vehicles

ABSTRACT

The invention relates to a mudguard for motor vehicles in general, comprising an external body ( 10 ) and an intrados ( 17 ) between which a curved cavity ( 16 ) extending from a front sector to a rear sector of the mudguard is defined, with reference to the wheel ( 2, 3 ) where it is mounted. The mudguard is further provided with a manifold ( 18 ) and a pair of deflectros ( 19, 20 ) which convey air into the cavity, so as to evacurate the water sprayed by the vehicle wheels and preventing sprays towards the outside.

BACKGROUND AND SUMMARY OF THE INVENTION

The invention relates to a mudguard for vehicles in general, such asmotor cars, lorries, trailers and the like.

In particular it relates to a hydro-expeller mudguard, i.e. a mudguardable to reduce water sprays and expel water drained from the wheelhousing during travel of a vehicle.

In the remainder of this description reference will be made, for thesake of brevity, to the water and the phenomena which arise in.connection with the travel of vehicles on wet roads: this, however, mustnot be understood as limiting the invention, which may also be appliedwith regard to the travel of vehicles on dry ground, since situationssimilar to those produced by water exist in the case of dust.

As is known, a situation which has important consequences for roadsafety is that caused by the water sprays of motor cars and lorriesespecially when travelling on wet roads.

In order to eliminate or in any case to reduce the negative effectsarising from the mass of nebulized water created by the wheels of thevehicles, several kinds of mudguard have been proposed.

In simplified terms it may be stated that the known mudguards may bedivided into two main categories: those where trapping of the spray isobtained by means of special surfaces applied inside the mudguard andthose where the effects of air currents circulating inside the wheelhousing are used, if necessary in combination with the abovementionedsurfaces.

Examples of mudguards of the first type are described in European patentapplications No. 528410 or No. 626308, while examples of the second typemay be found in the international patent applications PCT/IB95/00071 orPCT/EP91/00461.

Basically, in the first case the trapping action is due to the fact thatthe water raised by the tyres is retained by the internal surface of themudguard as a result of its configuration which prevents, or in any caselimits, rebounding of the droplets sprayed against it.

For this purpose the mudguard is provided with a cavity whose surfacefacing the tyre is perforated or formed as a grill or in any otherequivalent manner, so as to slow down and deviate the droplets towardsthe inside of the cavity wherefrom the water flows out because ofgravity.

However, the efficiency of the mudguards made in accordance with thisdesign depends also on the manner by which the water is evacuated fromthe cavity: therefore it follows that in the upper zone of the wheelhousing where the inclination of the surfaces is small, there may be anaccumulation or in any case poor drainage of the water, which limits thespray reducing effect of the entire system.

It is perhaps for this reason that such a solution seems to be adoptedpreferably in the rear zone of the known mudguards, which is ratherinclined in the vertical direction.

In the other type of mudguards mentioned above, the water droplets areevacuated by making use of an air flow inside the wheel housing.

In particular, in the second international patent application indicatedbefore there is disclosed a complex system for sucking the air and thewater spray from such housing, based on the Venturi effect produced byspecial channels present in the vehicle or by fans.

It can be understood that such a solution requires modifications to thevehicle (and not only to the mudguard), thereby resulting difficult tobe carried out on an industrial level and also expensive.

The present invention aims at overcoming the foregoing state of the art:namely, it has the object of providing a mudguard which reduces thewater spray or the dust raised by motor-vehicle wheels, with suchstructural and operating features as to overcome the limitations ofknown mudguards.

This object is achieved by a hydro-expeller mudguard, whosecharacterising features are set out in the claims which will follow.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be better understood in the light of the descriptionprovided hereinafter, relating to a preferred and non-exclusiveembodiment thereof illustrated in the accompanying drawings wherein:

FIG. 1 is a front view of a mudguard according to the invention appliedto the wheels of a vehicle;

FIGS. 2 and 3 show the above mudguard respectively from the right-handside and left-hand side, as indicated by the arrows D and S in FIG. 1;

FIG. 4 shows a perspective view of a part of the mudguard of FIGS. 1-3;

FIG. 5 shows in detail a particular feature of the abovementionedmudguard;

FIGS. 6, 7 are respective cross-sections along the lines VI-VI andVII-VII of FIG. 5.

DETAILED DESCRIPTION

As can be seen, the drawings show a hydro-expeller mudguard 1 inaccordance with this invention applied to a pair of twin wheels 2, 3 ofthe type commonly used in lorries or trailers thereof.

The mudguard 1 comprises an external semi-circular body 10, fixed to thevehicle in a manner known per se and not shown in the drawings, whichextends from the front side to the rear side of the wheels 2 and 3 withreference to the direction of travel indicated in FIG. 1.

The body 10 covers the wheels 2, 3 and includes a bottom surface 11 atthe side directed towards the inside of the vehicle, while at the frontit is closed by a cover 12 which may be opened in a manner similar to ahatch, being mounted with a hinge 13; in FIG. 1 this cover is shown witha continuous line in the open condition, while its profile is outlined(in the same figure) with broken lines in the closed condition.

An air inlet 15 which allows the entry of air from the outside towardsthe inside of the mudguard, is arranged on the top fore part of body 10.

In particular, a cavity 16 is defined inside the mudguard between theintrados 17 thereof and the external body, which communicates with theair inlet 15.

In accordance with this embodiment of the invention, the air whichenters into the mudguard 1 through the inlet 15 passes through aconverging manifold 18, where two deflectors 19 and 20 are located: thefirst of them is arranged upstream of the second one with reference tothe direction of the relative speed of the air with respect to themudguard, and deviates a part of the air flow towards the front sectorof the mudgards, inside the cavity 16.

The deflector 20 which is located downstream divides, instead, theremainder of the incoming air flow into two parts: one part is deviatedtowards the space between the intrados 17 and the wheels 2, 3, while theother part flows out towards the rear zone of the cavity 16.

For this purpose the deflector 20, which consists of a metal platefolded with a concave profile likewise the first deflector, leaves theupper portion of the cross-section of the manifold 18 open so that theair can flow freely therethrough, towards the rear zone of the cavity16.

In the rear and front sectors of the mudguard 1, fins 22 and 23 are alsopresent.

As can be seen, these fins are formed differently depending on whetherthey are arranged on one sector or the other of the mudguard: this is inorder to obtain a better retention effect of the water droplets sprayedby the wheels 2 and 3, along the whole of the semi-circular arch overwhich the mudguard extends.

The latter is provided, at the front, with a water collection channel 25which terminates towards the inner side of the vehicle (FIGS. 2 and 3),and at the rear with a discharge chamber 30.

It should be noted that the fact that the collection channel 25 projectstowards the inside of the vehicle beyond the wheel 3, prevents the waterthat flows out of it from falling into the rolling zone of the wheelswith the consequent further formation of sprays and possible problems ofgrip on the road surface.

The discharge chamber 30 has not only the function of reducing thesprays, as the normal protective devices mounted in the same position onthe known mudguards, but also that of retaining the sprays and drainingthe water flowing out of the cavity 16.

For this purpose the chamber 30 has a flattened box-shaped form tapereddownwards, in which two planar walls 31 and 32, i.e. a front one andrear one, are located facing and converging one another.

The front wall 31 is provided with holes 33 which, in this example, havea rectangular shape and are arranged in a matrix; the rear wall 32 isprovided on its surface directed towards the inside of the chamber 30,with a series of vertical ribs 34 which define thin channels (see FIG.7).

Advantageously, in this embodiment the chamber 30 comprises a resilientpleated band 36 which allows to absorb the accidental impacts with theground during the travel of the vehicle, as will be described in moredetail below.

This band is fixed at the top to the mudguard by means of rivets, boltsor similar systems indicated in the drawings by the reference number 37,while in accordance with a preferred embodiment, above the band there islocated a slit 38 having a fin 39 associated thereto, which allows thewater falling from above to be conveyed into the chamber 30; in order tocheck the condition of the mudguard and the presence of any obstructionspreventing drainage of the water into the discharge chamber, inspectionholes closed with plugs 40 have been provided above the latter.

The action of containing the spray in the vicinity of the road surfaceperformed by the discharge chamber 30 is supplemented by two sidewalls41 and 42 projecting frontally therefrom; in accordance with theinvention it has been found that the spray reduction efficiency isimproved by keeping the discharge chamber 30 in a substantially verticalposition.

For this purpose, in this example of mudguard the following suspensionsystem for the chamber has been provided.

As mentioned above, the resilient band ensures freedom of movement ofthe discharge chamber 30 in the vertical direction; it also makes thesystem flexible rotationally with respect to a horizontal axis X definedby a pair of pins 43 and 44 (cf FIG. 5), so as to be able to absorbbetter the impacts with the ground.

The aforementioned pins are rotationally supported on respectiveappendages 45, 46 of the body 10 of the mudguard and have fixed, attheir projecting ends, guides 47, 48 which extend along the sides of thedischarge chamber 30.

These guides are profiled sections with a C-shaped cross-section whichaccomodate, further to the pins 43 and 44, the studs 49 and 50 thatengage in respective grooves 51 and 52 formed in the side walls 53, 54of the discharge chamber 30 (in FIG. 5 the studs and grooves have beenrendered visible by removing a portion of the concerned zone).

In the case of impacts with the ground, owing to the flexibility of thepleated band 36, the chamber 30 may perform elastic movements from thebottom upwards and vice versa as indicated by the arrow in FIG. 6,guided by the engagement of the studs 49, 50 inside the grooves 53, 54.

Furthermore, the resilient band 36 allows the chamber 30 to perform alsoangular oscillations with respect to the axis X defined by the pins 43,44: indeed, in the case of impacts which exert a thrust in a directionperpendicular to the chamber 30 (i.e. perpendicular to the plane of FIG.5), the latter rotates elastically with respect to this axis with anangular amplitude which will depend on the entity of the thrust and onthe elastic properties of the pleated band 30.

In other words, the latter may function like a spring which impartseither an elastic reactive force in vertical direction and an elasticreturn torque with respect to the axis X, so as to avoid that thechamber 30 be excessively stressed in the event of impacts.

It should be noted, however, that in the normal operating condition thechamber 30 is in any case kept vertical because this ensures betterretention of the sprays.

In the light of what has been described hitherto it is possible tounderstand the mode of operation of the mudguard 1 according to theinvention.

When the vehicle on which the mudguard is mounted is moving, the airwhich enters through the inlet 15 into the manifold 18 because of thespeed, is deviated by the deflectors 19, 20 in two directions: the firstone towards the front part of the mudguard, between the intrados 17 withthe fins 23 and the body 10 as well as between the intrados and thewheels 2, 3, while the second towards the rear part of the cavity wherethe fins 22 extend.

It should be pointed out in this connection that the speed of theincoming air is accelerated following the Venturi effect provided by theconverging shape of the manifold 18, defined between the intrados 17 andits horizontal ceiling 18 a.

Meanwhile, the water raised by the wheels is sprayed partly towards thedischarge chamber 30, partly towards the fins 22 of the rear sector ofthe mudguard 1 and partly towards the fins 23 of the front sectorthereof.

The holes 33 present on the front of the discharge chamber 30 preventthe water droplets from rebounding off at high speed and producingspray: indeed, as a result of these holes the droplets can enter intothe chamber 30 where they are retained against the rear wall 32 thereof,owing to the effect provided by the ribs 34.

At the same time, the water droplets sprayed against the rear sector ofthe mudguard are intercepted by the fins 22 and sucked into the cavity16 by the air jet flowing inside it.

This suction effect is advantageously increased by the slight vacuuminduced in the air while it flows along the converging manifold 18.

All the water which collects inside the cavity 16 flows thereafterdownwards to the discharge chamber 30: the downwardly tapered shape ofthe latter and the presence of the thin channels formed by the ribs 34on the rear wall thereof, ensure that water coming out makes a uniformveil similar to a barrier which helps to stop the spray raised by thewheels.

A similar situation also arises in the front sector of the mudguard:indeed, also in this case the water droplets transported into this zoneby the wheels are sucked up by the air deviated by the deflectors 19 and20 respectively into the space between the intrados 17 (with the fins23) and the body 10, and into the space between the latter and thewheels 2, 3.

Unlike the rear sector, however, in this case the water which flowsdownwards is evacuated from the channel 25 on the inner side of thevehicle, thereby avoiding spray formation of towards the outsidethereof.

From this explanation it can therefore be understood how the circulationof air inside the mudguard in accordance with the teaching of thepresent invention, allows optimum evacuation of the water spray producedby the wheels, preventing it also from stagnating in the top part wherethe surfaces have a small inclination and the water therefore cannotflow properly.

In addition to this result, which is important per se, it must be addedthat the conveying of the air so obtained reduces the turbulence betweenthe mudguard and the wheels, which may cause the formation of waterspray towards the outside of the vehicle.

It should be noted in this connection that the front cover 12 performs auseful function in that it protects the mudguard (and the air flowinside it) from interference, due to turbulent external air flowsresulting from the speed of the vehicle.

Obviously variations of the invention with respect to its embodimentillustrated hereinbefore are possible.

By way of example, there could be provided on the bottom wall or on thefront cover 12 drainage channels such as those shown in broken lines inFIGS. 2 and 3 intended to collect the water sprayed against it.

Furthermore, also as regards the manner in which the air is conveyedtowards the front and rear sectors of the mudguard, several solutionsare possible.

For example it should be considered that in the case when air passing inthe space between the intrados and the wheels is not required, thedeflector 20 could be eliminated and the air could still flow in therear part of the cavity 16.

Moreover, there could also be provided a number of deflectors along themanifold 18 greater than two as disclosed in the above example, in orderto improve or in any case increase the air flow circulating inside themudguard; such a solution would be useful in the case of large-sizeapplications, like for lorries and similar vehicles.

In the same way it could be envisaged to provide several manifolds forconveying air into the front and rear sectors of the mudguard, insteadof the single one seen in the aforesaid embodiment.

For example, it would be possible to provide a mudguard in which thedeflectors 19, 20 and the single manifold 18, are replaced by aplurality of manifolds connected to the cavity 16 at the same point asthe deflectors and/or other points, so as to convey the air inaccordance with the teaching explained heretofore.

These and further variations nevertheless fall within the scope of thefollowing claims.

1. A mudguard for vehicles in general, comprising an external body andan intrados between which a curved cavity extending from a front sectorto a rear sector of the mudguard is defined with reference to a vehiclewheel, wherein the mudguard comprises at least one inlet for entry ofair into the cavity and means associated thereto for conveying air intoboth front and rear sectors, said air conveying means comprising amanifold extending substantially tangentially with respect to the cavityfrom the highest point thereof, and at least one deflector arrangedalong this manifold, the deflector being concave with the concavityfacing said air inlet for deviating a portion of the air flow enteringsaid at least one inlet towards the front sector of the cavity, andwherein the intrados further comprises fins disposed in the front andrear sectors.
 2. The mudguard of claim 1, further comprising means forconveying air between the front part of a wheel and the intrados.
 3. Themudguard of claim 1, wherein the manifold has a shape converging fromthe air inlet towards the cavity.
 4. The mudguard of claim 1, whereinthe deflector deviates a part of the air flow entering via the inlettowards the space between the front part of the wheel and the intradosof the mudguard.
 5. The mudguard of claim 1, wherein said air conveyingmeans further comprises a plurality of manifolds extending substantiallytransverse or tangential with respect to the cavity and connected to itat different points, so as to convey air along the front and rearsectors of the mudguard.
 6. The mudguard of claim 1, further comprisinga front protective cover hinged to the body and/or to the intrados. 7.The mudguard of claim 1, further comprising a discharge chamber locatedat the end of the rear sector and having a flattened box shape tapereddownwards with two flat walls, a front wall and a rear wall, arrangedfacing one another in a converging manner, in which the front wall isprovided with a plurality of holes.
 8. The mudguard of claim 7, whereinthe rear wall of the discharge chamber is provided with ribs arrangedside by side which define channels for draining the water downwards. 9.The mudguard of claim 7, wherein the discharge chamber is connected tothe rear sector of the mudguard by means of a resilient band so as to bemovable from the bottom upwards and vice versa.
 10. The mudguard ofclaim 9, wherein the discharge chamber is supported by pins so as toswing angularly with respect to a substantially horizontal axis.
 11. Themudguard of claim 9, wherein the resilient band is of pleated type. 12.The mudguard of claim 7, further comprising means for guiding themovements, from the bottom upwards and vice versa, of the dischargechamber.
 13. The mudguard of claim 12, wherein said guiding meanscomprise sections arranged on the side of the discharge chamber andstuds fixed to the sections, which engage in grooves arranged on thesides of the discharge chamber.